An apparatus for flanging and indenting both ends of a cylindrical container body, particularly for an aerosol or beverage can, is known in which the flanging and indenting occur in one operation.
This apparatus comprises two rotatably driven flanging and indenting heads slidable opposite to each other axially into the container body which are each provided with a radially slidable wobble disk centered on a conical member slidable against a spring.
Each flanging and indenting head is associated with a pivoting arm equipped with a flanging and indenting roller which is pivotable by at least one controlling cam about an axis running parallel to the rotation axis of the flanging and indenting roller so that the flanging and indenting roller is brought into and out of engagement with the wobble disk to form a flanged and indented edge of the container body.
The above described machine is described in Lanico brochure: "Bordel- und Eiziehautomat BEA 6-325". It is completely automatic and container bodies are fed into it in a horizontal orientation. Several planetlike circular stations with flanging and indenting heads as described above and associated pivoting arms and control cams are provided.
This machine has proved to be extraordinarily successful in practice for processing a cylindrical container body with a longitudinal weld seam. This type of container body is particularly used for making an aerosol or beverage can.
The known machine, however, is only suitable for processing metal sheet which has a sufficient elasticity. With a container body of metal sheet or too great hardness and/or for doubly reduced sheet the flanging and indenting process may not be completed in one operation.
However this sheet even tends to form tears on deformation when several operations are required. On the other hand there is considerable interest in being able to work hard and/or doubly reduced sheet since there are substantial economies derived from its use and the container body can be made with a thinner wall than is used in the conventional process.